SUB-ELEMENT E Flashcards
What is the voltage range considered to be valid logic low input in a TTL device operating at 5 volts?
A. 2.0 to 5.5 volts.
B. -2.0 to -5.5 volts.
C. Zero to 0.8 volts.
D. 5.2 to 34.8 volts.
C
What is the voltage range considered to be a valid logic high input in a TTL device operating at 5.0 volts?
A. 2.0 to 5.5 volts.
B. 1.5 to 3.0 volts.
C. 1.0 to 1.5 volts.
D. 5.2 to 34.8 volts.
A
What is the common power supply voltage for TTL series integrated circuits?
A. 12 volts.
B. 13.6 volts.
C. 1 volt.
D. 5 volts.
D
TTL inputs left open develop what logic state?
A. A high-logic state.
B. A low-logic state.
C. Open inputs on a TTL device are ignored.
D. Random high- and low-logic states.
A
Which of the following instruments would be best for checking a TTL logic circuit?
A. VOM.
B. DMM.
C. Continuity tester.
D. Logic probe.
D
What do the initials TTL stand for?
A. Resistor-transistor logic.
B. Transistor-transistor logic.
C. Diode-transistor logic.
D. Emitter-coupled logic.
B
What is a characteristic of an AND gate?
A. Produces a logic “0” at its output only if all inputs are logic “1”.
B. Produces a logic “1” at its output only if all inputs are logic “1”.
C. Produces a logic “1” at its output if only one input is a logic “1”.
D. Produces a logic “1” at its output if all inputs are logic “0”.
B
What is a characteristic of a NAND gate?
A. Produces a logic “0” at its output only when all inputs are logic “0”.
B. Produces a logic “1” at its output only when all inputs are logic “1”.
C. Produces a logic “0” at its output if some but not all of its inputs are logic “1”.
D. Produces a logic “0” at its output only when all inputs are logic “1”.
D
What is a characteristic of an OR gate?
A. Produces a logic “1” at its output if any input is logic “1”.
B. Produces a logic “0” at its output if any input is logic “1”.
C. Produces a logic “0” at its output if all inputs are logic “1”.
D. Produces a logic “1” at its output if all inputs are logic “0”.
A
What is a characteristic of a NOR gate?
A. Produces a logic “0” at its output only if all inputs are logic “0”.
B. Produces a logic “1” at its output only if all inputs are logic “1”.
C. Produces a logic “0” at its output if any or all inputs are logic “1”.
D. Produces a logic “1” at its output if some but not all of its inputs are logic “1”.
C
What is a characteristic of a NOT gate?
A. Does not allow data transmission when its input is high.
B. Produces a logic “0” at its output when the input is logic “1” and vice versa.
C. Allows data transmission only when its input is high.
D. Produces a logic “1” at its output when the input is logic “1” and vice versa.
B
Which of the following logic gates will provide an active high out when both inputs are active high?
A. NAND.
B. NOR.
C. AND.
D. XOR.
C
In a negative-logic circuit, what level is used to represent a logic 0?
A. Low level. C. Negative-transition level.
B. Positive-transition level. D. High level.
D
For the logic input levels shown in Figure 3E12, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is high, B is low and C is low.
B. A is low, B is high and C is high.
C. A is high, B is high and C is low.
D. A is low, B is high and C is low.
B
For the logic input levels given in Figure 3E13, what are the logic levels of test points A, B and C in this circuit? (Assume positive logic.)
A. A is low, B is low and C is high.
B. A is low, B is high and C is low.
C. A is high, B is high and C is high.
D. A is high, B is low and C is low.
C
In a positive-logic circuit, what level is used to represent a logic 1?
A. High level
B. Low level
C. Positive-transition level
D. Negative-transition level
A
Given the input levels shown in Figure 3E14 and assuming positive logic devices, what would the output be?
A. A is low, B is high and C is high. C. A is low, B is low and C is high.
B. A is high, B is high and C is low. D. None of the above are correct.
A
What is a truth table?
A. A list of input combinations and their corresponding outputs that characterizes a digital device’s function.
B. A table of logic symbols that indicate the high logic states of an op-amp.
C. A diagram showing logic states when the digital device’s output is true.
D. A table of logic symbols that indicates the low logic states of an op-amp.
A
A flip-flop circuit is a binary logic element with how many stable states?
A. 1
B. 2
C. 4
D. 8
B